Generally, when a person having a wound with a medical dressing or a cast is to shower or bath, a water impervious barrier such as plastic sheeting is used to cover the area. A typical form of dressing is the use of a garbage bag or plastic grocery bag, tied, rubber-banded or taped at the opening in an attempt to create a waterproof covering. Tape is often used to seal the edges in an attempt to make the area airtight or waterproof. Such arrangements tend to leak, particularly when the wound is at a location where bending or movement of the body occurs.
Frequently, these methods are ineffective at best and potentially harmful to the wearer at worst and render the item useless after a single use.
Liquid barriers have been described that use elastic bands to create a water barrier. See, e.g., U.S. Pat. No. 7,290,290. Often, it is used as a strip, wrapped around the limb, similar to the use of a tourniquet. In addition to not always forming a water tight seal, this approach to using elastic could be harmful to the wearer if overtightened or left on too long, particularly by those wearers with diseases, such as diabetes, who have circulatory problems.
Liquid barriers also have been described that use adhesive strips to form a watertight seal. See, e.g., U.S. Pat. No. 5,152,282. The barrier is a single sheet open on all sides, which may allow water to flow under the sheet and to interfere with the adhesive, thereby causing water to come in contact with the wound.